As described in U.S. Pat. Nos. 5,422,822; 4,425,365; 6,725,477; and 4,651,371 various bed linens have been provided for top bed sheets with a pocket type end portion that is adapted to fit around the end of a mattress. The purpose of these fitted bed sheets is to provide a contour sheet that does not easily slide off the mattress and remains flat and tight to the mattress.
Moreover, US Patent Application Publication Serial Nos. 2004/0200000 and 2006/0168726 describe fitted top bed sheets with a fitted end.
None of the above mentioned bed sheets are provided with any kind of elasticized material or elastic at the pocket end of the bed sheet.
However with respect to U.S. Pat. No. 5,165,128, a fitted top bed sheet is provided with a rectangular portion of fabric material having two bottom corners, with each corner cut away by three curved lines to form a junction having an angle of substantially 90°, to each of which a band of stretchable material is sewn that extends across the entire outside edge of that portion of the bed sheet, thereby to draw in the corners of the bed sheet at the foot of the bed sheet.
More importantly and as described in U.S. Pat. No. 7,380,279, a fitted bed top covering is provided with a pocket that is made of elastic material such as Spandex®, a polyurethane-polyurea copolymer surrounding the end of the mattress.
In this patent it is said that the pocket that is made of the expandable material has a pocket opening that is larger in size than the extent of the mattress foot that it encases. It is said that the purpose of this increased size opening is to create a so-called zone of expansion at the foot end of the sheet to accommodate the feet of a sleeping individual.
One of the problems with such an arrangement is that the wide opening of the pocket results in a large amount of unstretched material at the foot of the bed sheet, with the unstretched material accommodating an individual's feet. It is noted that the unstretched material creates an unsightly wrinkled sheet appearance when the bed is made up.
While the pocket is enlarged for purposes of permitting an individual's feet to extend above the mattress without sheet tension on the toes, this same amount of material which is left over from the oversized aperture of the pocket creates a messy appearance. As such the sheet is unsuitable for use in commercial establishments such as hotels and motels because of its unsightly and wrinkled appearance when the bed is made up.
While several of the above-mentioned patents have elasticized material around all edges of the pocket, this elasticized pocket, whether made of Spandex®, a polyurethane-polyurea copolymer or material sewn in the seams, provides undue pressure on a sleeping individual's toes that may interfere with sleep.
Of course, if the expanded pocket aperture size creates a non-stretched amount of material at the foot of the sheet in an effort to avoid having the top sheet compressed around the individual's toes, the messy result is not a commercially viable solution.
With respect to bed sheets that have elastic material around all edges of the bed sheet, while providing a flat unwrinkled bed sheet at the foot of the bed sheet, the amount of elasticized material prevents an individual's toes from poking the bed sheet up when the individual is sleeping.
In short, with a totally elasticized pocket for a top fitted bed sheet the individual is subjected to undesirable sheet pressure on his or her toes when the individual is sleeping.